For most of the season, Johnson has held back the Jayhawks offense. The offensive rating statistic (using a long but trusted formula) tells us how many points a player produces per 100 possessions on his own. This number is used with usage percentage, which tells what percentage of a team's possessions a player ends (average is 20 percent).

The following chart shows the top six KU players' offensive ratings compared to their usage percentages. Players toward the right are the most efficient, while the players toward the top are taking the biggest offensive roles for KU.

The graph shows that Johnson has been KU's most inefficient player by a wide margin. Compounding the problem is that he has the second-highest usage percentage, meaning lots of KU's possessions are ending in the hands of its worst offensive player.

Johnson's numbers also don't compare well to other starting point guards under KU coach Bill Self*.

* — I picked Sherron Collins as KU's point guard in 2009-10 over Tyshawn Taylor, though you could make an argument either way.

Yes, Johnson is shooting a few more two-point jumpers this year, which will bring down his efficiency some. And while shooting fewer three-pointers, his accuracy from long range is still below the NCAA average.

But the glaring number here is Johnson's field-goal percentage on close shots. While shooting a similar percentage of dunks, tipins and layups, Johnson's shooting percentage is down 19 percentage points from a year ago.

What's the reason for this?

It could go back to the position he's playing. Because he's the point guard and not a shooting guard, he's on the delivering end of fast breaks instead of the receiving end.

Here's a comparison of the close shots Johnson has been assisted on this season compared to last.

Johnson doesn't appear to be getting many of the easy baskets he did last year because of his change in roles. Because most assisted baskets come without a dribble, this might also hint that Johnson is more comfortable scoring without putting the ball on the floor.

The switch to point guard also has sapped another part of Johnson's offensive game from a year ago: alley-oops.

According to the KU Athletics game notes, Johnson had 15 dunks in 2011-12. This year, he has three.

Self likes to talk about how players get shooting confidence by making easy shots, and Johnson hasn't had many chances for those as the primary ballhandler. We did see the Jayhawks try to get Johnson an alley-oop on the first possession against Oklahoma State, but Jeff Withey's pass was knocked away for a turnover.

There might be another reason for Johnson struggling on close shots: He might be trying to avoid contact.

Johnson was just 2-for-6 on layup and dunk tries against OSU, and in this video and also this one, he appears to be shying away from contact* as he gets to the rim while also worrying too much about shot-blockers.

Compare those clips to the first 1 1/2 minutes of this video, which shows Johnson's confident drives from the NCAA Tournament last year.

* — I also can't help but think of the Oregon State game, when Johnson went aggressively to the basket before getting fouled and knocked on his tailbone. A play like that could (for good reason) make someone less likely to be aggressive at the rim.

Johnson's efficiency also has been negatively affected by turnovers.

We can see this best if we look at his turnover rate, which measures what percentage of his ended possessions that are used on turnovers.

Johnson appears to especially be struggling with turnovers since his switch back to point guard. Let's compare his turnover rate numbers to those of Tyshawn Taylor, who also was widely criticized for giving the ball away too often.

Johnson's assist rate has spiked this year (he's 136th nationally), but it has come at a steep price, as his turnover rate has soared as well.

Unfortunately for KU, there doesn't appear to be an easy solution.

Tharpe's efficiency numbers are better than Johnson's, but not by a lot. Playing Tharpe more often would result in better offense for KU now, but it also could result in dwindling confidence for Johnson, who was one of KU's best two players (along with Withey) during last year's run to the national championship game.

Self also could put Tharpe in at the 1 and move Johnson back to his natural position at the 2, but that would mean he would have to take one of his two best players off the floor (Ben McLemore or Travis Releford) or he'd have to play Releford out of position at the 4. Doing that would mean Releford — a talented on-ball defender — would have to guard a big man inside.

Because McLemore and Releford are not good ballhandlers — and because KU's ceiling remains highest with Johnson on the floor — Self appears to be ready to stick Johnson back in there with the hope he turns things around.

If he does, it'll most likely be because he increases his efficiency on close shots or limits his turnovers to the point that he once again becomes a valuable player for KU.